[PATCH 5.12 601/677] net: ethernet: ixp4xx: Set the DMA masks explicitly

From: Greg Kroah-Hartman
Date: Wed May 12 2021 - 15:19:26 EST


From: Linus Walleij <linus.walleij@xxxxxxxxxx>

[ Upstream commit 8d892d60941b00c86d2029c8a99db24ab4979673 ]

The former fix only papered over the actual problem: the
ethernet core expects the netdev .dev member to have the
proper DMA masks set, or there will be BUG_ON() triggered
in kernel/dma/mapping.c.

Fix this by simply copying dma_mask and dma_mask_coherent
from the parent device.

Fixes: e45d0fad4a5f ("net: ethernet: ixp4xx: Use parent dev for DMA pool")
Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ethernet/xscale/ixp4xx_eth.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/xscale/ixp4xx_eth.c b/drivers/net/ethernet/xscale/ixp4xx_eth.c
index 0152f1e70783..9defaa21a1a9 100644
--- a/drivers/net/ethernet/xscale/ixp4xx_eth.c
+++ b/drivers/net/ethernet/xscale/ixp4xx_eth.c
@@ -1085,7 +1085,7 @@ static int init_queues(struct port *port)
int i;

if (!ports_open) {
- dma_pool = dma_pool_create(DRV_NAME, port->netdev->dev.parent,
+ dma_pool = dma_pool_create(DRV_NAME, &port->netdev->dev,
POOL_ALLOC_SIZE, 32, 0);
if (!dma_pool)
return -ENOMEM;
@@ -1435,6 +1435,9 @@ static int ixp4xx_eth_probe(struct platform_device *pdev)
ndev->netdev_ops = &ixp4xx_netdev_ops;
ndev->ethtool_ops = &ixp4xx_ethtool_ops;
ndev->tx_queue_len = 100;
+ /* Inherit the DMA masks from the platform device */
+ ndev->dev.dma_mask = dev->dma_mask;
+ ndev->dev.coherent_dma_mask = dev->coherent_dma_mask;

netif_napi_add(ndev, &port->napi, eth_poll, NAPI_WEIGHT);

--
2.30.2